pillow_heif.misc — pillow-heif 1.4.0 documentation

# Source code for pillow_heif.misc

    """Different miscellaneous helper functions.

    Mostly for internal use, so prototypes can change between versions.
    """

    import builtins
    import re
    from dataclasses import dataclass
    from enum import IntEnum
    from math import ceil
    from pathlib import Path
    from struct import pack, unpack

    from PIL import Image

    from . import options
    from .constants import HeifChannel, HeifChroma, HeifColorspace, HeifCompressionFormat

    try:
        import _pillow_heif
    except ImportError as ex:
        from ._deffered_error import DeferredError

        _pillow_heif = DeferredError(ex)

    MODE_INFO = {
        # name -> [channels, bits per pixel channel, colorspace, chroma]
        "BGRA;16": (4, 16, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "BGRa;16": (4, 16, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "BGR;16": (3, 16, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBB_LE),
        "RGBA;16": (4, 16, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "RGBa;16": (4, 16, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "RGB;16": (3, 16, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBB_LE),
        "LA;16": (2, 16, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "La;16": (2, 16, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "L;16": (1, 16, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "I;16": (1, 16, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "I;16L": (1, 16, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "BGRA;12": (4, 12, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "BGRa;12": (4, 12, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "BGR;12": (3, 12, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBB_LE),
        "RGBA;12": (4, 12, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "RGBa;12": (4, 12, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "RGB;12": (3, 12, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBB_LE),
        "LA;12": (2, 12, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "La;12": (2, 12, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "L;12": (1, 12, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "I;12": (1, 12, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "I;12L": (1, 12, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "BGRA;10": (4, 10, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "BGRa;10": (4, 10, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "BGR;10": (3, 10, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBB_LE),
        "RGBA;10": (4, 10, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "RGBa;10": (4, 10, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBBAA_LE),
        "RGB;10": (3, 10, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RRGGBB_LE),
        "LA;10": (2, 10, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "La;10": (2, 10, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "L;10": (1, 10, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "I;10": (1, 10, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "I;10L": (1, 10, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "RGBA": (4, 8, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RGBA),
        "RGBa": (4, 8, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RGBA),
        "RGB": (3, 8, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RGB),
        "BGRA": (4, 8, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RGBA),
        "BGRa": (4, 8, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RGBA),
        "BGR": (3, 8, HeifColorspace.RGB, HeifChroma.INTERLEAVED_RGB),
        "LA": (2, 8, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "La": (2, 8, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "L": (1, 8, HeifColorspace.MONOCHROME, HeifChroma.MONOCHROME),
        "YCbCr": (3, 8, HeifColorspace.YCBCR, HeifChroma.CHROMA_444),
    }

    SUBSAMPLING_CHROMA_MAP = {
        "4:4:4": 444,
        "4:2:2": 422,
        "4:2:0": 420,
    }

    LIBHEIF_CHROMA_MAP = {
        1: 420,
        2: 422,
        3: 444,
    }

    def save_colorspace_chroma(c_image, info: dict) -> None:
        """Converts `chroma` value from `c_image` to useful values and stores them in ``info`` dict."""
        # Saving of `colorspace` was removed, as currently is not clear where to use that value.
        chroma = LIBHEIF_CHROMA_MAP.get(c_image.chroma)
        if chroma is not None:
            info["chroma"] = chroma

    def set_orientation(info: dict) -> int | None:
        """Reset orientation in ``EXIF`` to ``1`` if any orientation present.

        Removes ``XMP`` orientation tag if it is present.
        In Pillow plugin mode, it is called automatically for images.
        When ``pillow_heif`` used in ``standalone`` mode, if you wish, you can call it manually.

        .. note:: If there is no orientation tag, this function will not add it and do nothing.

            If both XMP and EXIF orientation tags are present, EXIF orientation tag will be returned,
            but both tags will be removed.

        :param info: `info` dictionary from :external:py:class:`~PIL.Image.Image` or :py:class:`~pillow_heif.HeifImage`.
        :returns: Original orientation or None if it is absent.
        """
        return _get_orientation(info, True)

    def _get_orientation_for_encoder(info: dict) -> int:
        image_orientation = _get_orientation(info, False)
        return 1 if image_orientation is None else image_orientation

    def _get_orientation_xmp(info: dict, exif_orientation: int | None, reset: bool = False) -> int | None:
        xmp_orientation = 1
        if info.get("xmp"):
            xmp_data = info["xmp"].rsplit(b"\x00", 1)
            if xmp_data[0]:
                decoded_xmp_data = None
                for encoding in ("utf-8", "latin1"):
                    try:
                        decoded_xmp_data = xmp_data[0].decode(encoding)
                        break
                    except Exception:  # noqa # pylint: disable=broad-except
                        pass
                if decoded_xmp_data:
                    match = re.search(r'tiff:Orientation(="|>)([0-9])', decoded_xmp_data)
                    if match:
                        xmp_orientation = int(match[2])
                        if reset:
                            decoded_xmp_data = re.sub(r'tiff:Orientation="([0-9])"', "", decoded_xmp_data)
                            decoded_xmp_data = re.sub(r"<tiff:Orientation>([0-9])</tiff:Orientation>", "", decoded_xmp_data)
                    # should encode in "utf-8" anyway, as `defusedxml` do not work with `latin1` encoding.
                    if encoding != "utf-8" or xmp_orientation != 1:
                        info["xmp"] = b"".join([decoded_xmp_data.encode("utf-8"), b"\x00" if len(xmp_data) > 1 else b""])
        return xmp_orientation if exif_orientation is None and xmp_orientation != 1 else None

    def _get_orientation(info: dict, reset: bool = False) -> int | None:
        original_orientation = None
        if info.get("exif"):
            try:
                tif_tag = info["exif"]
                skipped_exif00 = False
                if tif_tag.startswith(b"Exif\x00\x00"):
                    skipped_exif00 = True
                    tif_tag = tif_tag[6:]
                endian_mark = "<" if tif_tag[0:2] == b"\x49\x49" else ">"
                pointer = unpack(endian_mark + "L", tif_tag[4:8])[0]
                tag_count = unpack(endian_mark + "H", tif_tag[pointer : pointer + 2])[0]
                offset = pointer + 2
                for tag_n in range(tag_count):
                    pointer = offset + 12 * tag_n
                    if unpack(endian_mark + "H", tif_tag[pointer : pointer + 2])[0] != 274:
                        continue
                    value = tif_tag[pointer + 8 : pointer + 12]
                    t_original_orientation = unpack(endian_mark + "H", value[0:2])[0]
                    if t_original_orientation != 1:
                        original_orientation = t_original_orientation
                        if not reset:
                            break
                        p_value = pointer + 8
                        if skipped_exif00:
                            p_value += 6
                        new_orientation = pack(endian_mark + "H", 1)
                        info["exif"] = info["exif"][:p_value] + new_orientation + info["exif"][p_value + 2 :]
                        break
            except Exception:  # noqa # pylint: disable=broad-except
                pass
        xmp_orientation = _get_orientation_xmp(info, original_orientation, reset=reset)
        return xmp_orientation or original_orientation

    def get_file_mimetype(fp) -> str:
        """Gets the MIME type of the HEIF(or AVIF) object.

        :param fp: A filename (string), pathlib.Path object, file object or bytes.
            The file object must implement ``file.read``, ``file.seek`` and ``file.tell`` methods,
            and be opened in binary mode.
        :returns: "image/heic", "image/heif", "image/heic-sequence", "image/heif-sequence",
            "image/avif", "image/avif-sequence" or "".
        """
        heif_brand = _get_bytes(fp, 12)[8:]
        if heif_brand:
            if heif_brand == b"avif":
                return "image/avif"
            if heif_brand == b"avis":
                return "image/avif-sequence"
            if heif_brand in (b"heic", b"heix", b"heim", b"heis"):
                return "image/heic"
            if heif_brand in (b"hevc", b"hevx", b"hevm", b"hevs"):
                return "image/heic-sequence"
            if heif_brand == b"mif1":
                return "image/heif"
            if heif_brand == b"msf1":
                return "image/heif-sequence"
        return ""

    def _get_bytes(fp, length=None) -> bytes:
        if isinstance(fp, (str, Path)):
            with builtins.open(fp, "rb") as file:
                return file.read(length or -1)
        if hasattr(fp, "read"):
            offset = fp.tell() if hasattr(fp, "tell") else None
            result = fp.read(length or -1)
            if offset is not None and hasattr(fp, "seek"):
                fp.seek(offset)
            return result
        return bytes(fp)[:length]

    def _retrieve_exif(metadata: list[dict]) -> bytes | None:
        result = None
        purge = []
        for i, md_block in enumerate(metadata):
            if md_block["type"] == "Exif":
                purge.append(i)
                skip_size = int.from_bytes(md_block["data"][:4], byteorder="big", signed=False)
                skip_size += 4  # skip 4 bytes with offset
                if len(md_block["data"]) - skip_size <= 4:  # bad EXIF data, skip first 4 bytes
                    skip_size = 4
                elif skip_size >= 6 and md_block["data"][skip_size - 6 : skip_size] == b"Exif\x00\x00":
                    skip_size -= 6
                data = md_block["data"][skip_size:]
                if not result and data:
                    result = data
        for i in reversed(purge):
            del metadata[i]
        return result

    def _retrieve_xmp(metadata: list[dict]) -> bytes | None:
        result = None
        purge = []
        for i, md_block in enumerate(metadata):
            if md_block["type"] == "mime":
                purge.append(i)
                if not result:
                    result = md_block["data"]
        for i in reversed(purge):
            del metadata[i]
        return result

    def _exif_from_pillow(img: Image.Image) -> bytes | None:
        if "exif" in img.info:
            return img.info["exif"]
        if hasattr(img, "getexif"):  # noqa
            exif = img.getexif()
            if exif:
                return exif.tobytes()
        return None

    def _xmp_from_pillow(img: Image.Image) -> bytes | None:
        im_xmp = None
        if "xmp" in img.info:
            im_xmp = img.info["xmp"]
        elif "XML:com.adobe.xmp" in img.info:  # PNG
            im_xmp = img.info["XML:com.adobe.xmp"]
        if isinstance(im_xmp, str):
            im_xmp = im_xmp.encode("utf-8")
        return im_xmp

    def _pil_to_supported_mode(img: Image.Image) -> Image.Image:
        # We support "YCbCr" for encoding in Pillow plugin mode and do not call this function.
        if img.mode == "P":
            mode = "RGBA" if img.info.get("transparency", None) is not None else "RGB"
            img = img.convert(mode=mode)
        elif img.mode == "I":
            img = img.convert(mode="I;16L")
        elif img.mode == "1":
            img = img.convert(mode="L")
        elif img.mode == "CMYK":
            img = img.convert(mode="RGBA")
        elif img.mode == "YCbCr":
            img = img.convert(mode="RGB")
        return img

    class Transpose(IntEnum):
        """Temporary workaround till we support old Pillows, remove this when a minimum Pillow version will have this."""

        FLIP_LEFT_RIGHT = 0
        FLIP_TOP_BOTTOM = 1
        ROTATE_90 = 2
        ROTATE_180 = 3
        ROTATE_270 = 4
        TRANSPOSE = 5
        TRANSVERSE = 6

    def _rotate_pil(img: Image.Image, orientation: int) -> Image.Image:
        # Probably need create issue in Pillow to add support
        # for info["xmp"] or `getxmp()` for ImageOps.exif_transpose and remove this func.
        method = {
            2: Transpose.FLIP_LEFT_RIGHT,
            3: Transpose.ROTATE_180,
            4: Transpose.FLIP_TOP_BOTTOM,
            5: Transpose.TRANSPOSE,
            6: Transpose.ROTATE_270,
            7: Transpose.TRANSVERSE,
            8: Transpose.ROTATE_90,
        }.get(orientation)
        if method is not None:
            return img.transpose(method)
        return img

    def _get_primary_index(some_iterator, primary_index: int | None) -> int:
        primary_attrs = [_.info.get("primary", False) for _ in some_iterator]
        if primary_index is None:
            primary_index = 0
            for i, v in enumerate(primary_attrs):
                if v:
                    primary_index = i
        elif primary_index == -1 or primary_index >= len(primary_attrs):
            primary_index = len(primary_attrs) - 1
        return primary_index

    def __get_camera_intrinsic_matrix(values: tuple | None):
        return (
            {
                "focal_length_x": values[0],
                "focal_length_y": values[1],
                "principal_point_x": values[2],
                "principal_point_y": values[3],
                "skew": values[4],
            }
            if values
            else None
        )

    def _get_heif_meta(c_image) -> dict:
        r = {}
        camera_intrinsic_matrix = __get_camera_intrinsic_matrix(c_image.camera_intrinsic_matrix)
        if camera_intrinsic_matrix:
            r["camera_intrinsic_matrix"] = camera_intrinsic_matrix
        camera_extrinsic_matrix_rot = c_image.camera_extrinsic_matrix_rot
        if camera_extrinsic_matrix_rot:
            r["camera_extrinsic_matrix_rot"] = camera_extrinsic_matrix_rot
        return r

    class CtxEncode:
        """Encoder bindings from python to python C module."""

        def __init__(self, compression_format: HeifCompressionFormat, **kwargs):
            quality = kwargs.get("quality", options.QUALITY)
            self.ctx_write = _pillow_heif.CtxWrite(
                compression_format,
                -2 if quality is None else quality,
                options.PREFERRED_ENCODER.get("HEIF" if compression_format == HeifCompressionFormat.HEVC else "AVIF", ""),
            )
            enc_params = kwargs.get("enc_params", {})
            chroma = None
            if "subsampling" in kwargs:
                chroma = SUBSAMPLING_CHROMA_MAP.get(kwargs["subsampling"])
            if chroma is None:
                chroma = kwargs.get("chroma")
            if chroma:
                enc_params["chroma"] = chroma
            for key, value in enc_params.items():
                self.ctx_write.set_parameter(key, value if isinstance(value, str) else str(value))

        def add_image(self, size: tuple[int, int], mode: str, data, **kwargs) -> None:
            """Adds image to the encoder."""
            if size[0] <= 0 or size[1] <= 0:
                raise ValueError("Empty images are not supported.")
            bit_depth_in = MODE_INFO[mode][1]
            bit_depth_out = 8 if bit_depth_in == 8 else kwargs.get("bit_depth", 16)
            if bit_depth_out == 16:
                bit_depth_out = 12 if options.SAVE_HDR_TO_12_BIT else 10
            premultiplied_alpha = int(mode.split(sep=";")[0][-1] == "a")
            # creating image
            im_out = self.ctx_write.create_image(size, MODE_INFO[mode][2], MODE_INFO[mode][3], premultiplied_alpha)
            # image data
            if MODE_INFO[mode][0] == 1:
                im_out.add_plane_l(size, bit_depth_out, bit_depth_in, data, kwargs.get("stride", 0), HeifChannel.CHANNEL_Y)
            elif MODE_INFO[mode][0] == 2:
                im_out.add_plane_la(size, bit_depth_out, bit_depth_in, data, kwargs.get("stride", 0))
            else:
                im_out.add_plane(size, bit_depth_out, bit_depth_in, data, mode.find("BGR") != -1, kwargs.get("stride", 0))
            self._finish_add_image(im_out, size, **kwargs)

        def add_image_ycbcr(self, img: Image.Image, **kwargs) -> None:
            """Adds image in `YCbCR` mode to the encoder."""
            # creating image
            im_out = self.ctx_write.create_image(img.size, MODE_INFO[img.mode][2], MODE_INFO[img.mode][3], 0)
            # image data
            for i in (HeifChannel.CHANNEL_Y, HeifChannel.CHANNEL_CB, HeifChannel.CHANNEL_CR):
                im_out.add_plane_l(img.size, 8, 8, bytes(img.getdata(i)), kwargs.get("stride", 0), i)
            self._finish_add_image(im_out, img.size, **kwargs)

        def _finish_add_image(self, im_out, size: tuple[int, int], **kwargs):
            # set ICC color profile
            icc_profile = kwargs.get("icc_profile")
            if icc_profile is not None:
                im_out.set_icc_profile(kwargs.get("icc_profile_type", "prof"), icc_profile)
            # set NCLX color profile
            if kwargs.get("nclx_profile"):
                im_out.set_nclx_profile(
                    *[
                        kwargs["nclx_profile"][i]
                        for i in ("color_primaries", "transfer_characteristics", "matrix_coefficients", "full_range_flag")
                    ]
                )
            # set pixel aspect ratio
            pixel_aspect_ratio = kwargs.get("pixel_aspect_ratio")
            if pixel_aspect_ratio:
                im_out.set_pixel_aspect_ratio(pixel_aspect_ratio[0], pixel_aspect_ratio[1])
            # encode
            image_orientation = kwargs.get("image_orientation", 1)
            save_nclx = kwargs.get("save_nclx_profile", options.SAVE_NCLX_PROFILE)
            nclx_keys = ("color_primaries", "transfer_characteristics", "matrix_coefficients", "full_range_flag")
            has_explicit_nclx = any(k in kwargs for k in nclx_keys)
            # When NCLX saving is enabled and no existing NCLX profile is on the image and no explicit NCLX parameters
            # were provided, write an NCLX box that matches libheif internal sRGB encoding defaults.
            # Without this, no NCLX box is written and viewers must guess the color space, which causes color shifts.
            # See issue #365.
            # Values match libheif nclx_profile::set_sRGB_defaults() exactly:
            #   primaries=1 (BT.709)
            #   transfer=13 (sRGB)
            #   matrix=6 (BT.601)
            #   full_range=1
            if save_nclx and not kwargs.get("nclx_profile") and not has_explicit_nclx:
                color_primaries = 1  # BT.709
                transfer_characteristics = 13  # sRGB (IEC 61966-2-1)
                matrix_coefficients = 6  # BT.601-6
                full_range_flag = 1
            else:
                color_primaries = kwargs.get("color_primaries", -1)
                transfer_characteristics = kwargs.get("transfer_characteristics", -1)
                matrix_coefficients = kwargs.get("matrix_coefficients", -1)
                full_range_flag = kwargs.get("full_range_flag", -1)
            im_out.encode(
                self.ctx_write,
                kwargs.get("primary", False),
                save_nclx,
                color_primaries,
                transfer_characteristics,
                matrix_coefficients,
                full_range_flag,
                image_orientation,
            )
            # adding metadata
            exif = kwargs.get("exif")
            if exif is not None:
                if isinstance(exif, Image.Exif):
                    exif = exif.tobytes()
                im_out.set_exif(self.ctx_write, exif)
            xmp = kwargs.get("xmp")
            if xmp is not None:
                im_out.set_xmp(self.ctx_write, xmp)
            for metadata in kwargs.get("metadata", []):
                im_out.set_metadata(self.ctx_write, metadata["type"], metadata["content_type"], metadata["data"])
            # adding thumbnails
            for thumb_box in kwargs.get("thumbnails", []):
                if max(size) > thumb_box > 3:
                    im_out.encode_thumbnail(self.ctx_write, thumb_box, image_orientation)

        def save(self, fp) -> None:
            """Ask encoder to produce output based on previously added images."""
            data = self.ctx_write.finalize()
            if isinstance(fp, (str, Path)):
                Path(fp).write_bytes(data)
            elif hasattr(fp, "write"):
                fp.write(data)
            else:
                raise TypeError("`fp` must be a path to file or an object with `write` method.")

    @dataclass
    class MimCImage:
        """Mimicry of the HeifImage class."""

        def __init__(self, mode: str, size: tuple[int, int], data: bytes, **kwargs):
            self.mode = mode
            self.size = size
            self.stride: int = kwargs.get("stride", size[0] * MODE_INFO[mode][0] * ceil(MODE_INFO[mode][1] / 8))
            self.data = data
            self.metadata: list[dict] = []
            self.color_profile = None
            self.thumbnails: list[int] = []
            self.depth_image_list: list = []
            self.aux_image_ids: list[int] = []
            self.primary = False
            self.chroma = HeifChroma.UNDEFINED.value
            self.colorspace = HeifColorspace.UNDEFINED.value
            self.pixel_aspect_ratio = None
            self.camera_intrinsic_matrix = None
            self.camera_extrinsic_matrix_rot = None

        @property
        def size_mode(self):
            """Mimicry of c_image property."""
            return self.size, self.mode

        @property
        def bit_depth(self) -> int:
            """Return bit-depth based on image mode."""
            return MODE_INFO[self.mode][1]

    def load_libheif_plugin(plugin_path: str | Path) -> None:
        """Load specified LibHeif plugin."""
        _pillow_heif.load_plugin(plugin_path)